Income Taxes - Temporary Differences (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Valuation Allowance [Line Items]
Insurance reserves	$ 107	$ 74
Investments	23	79
Compensation and benefits	57	58
Other assets	34	34
Total gross assets	221	245
Net unrealized investment (gains) losses	(424)	(45)
Deferred policy acquisition costs	(101)	(205)
Total gross liabilities	(525)	(250)
Net deferred income tax asset (liability)	(304)	(5)
SEC Schedule, 12-09, Valuation Allowance, Operating Loss Carryforward
Valuation Allowance [Line Items]
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	0	9	$ (5)
Deferred Tax Asset, Capital Loss Carryforward
Valuation Allowance [Line Items]
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$ 0	$ 9	$ 0